Atomic layer deposition is known as a method for (repeated) depositing of a monolayer of target material. Atomic layer deposition differs from for example chemical vapour deposition in that atomic layer deposition takes at least two process steps. A first one of these process steps comprises application of a precursor gas on the substrate surface. A second one of these process steps comprises reaction of the precursor material in order to form the monolayer of target material. Atomic layer deposition has the advantage of enabling a good layer thickness control.
WO2008/085474 discloses an apparatus for deposition of atom layers. The apparatus discloses an air bearing effect so that a substrate hovers above an injector head. For sheeted substrates, such hovering may be an inefficient way to use precursor gas, where a risk of contamination is present and layers may be deposited less accurately.